A LEADING Birmingham obesity doctor warned a “fat tax” on junk snacks would only work if the Government cut the price of healthy food too.

Consultant Shahrad Taheri, an obesity expert at Heartlands Hospital, welcomed the government’s proposals to place a surcharge on foods containing more than 2.3 per cent saturated fat – similar to a scheme introduced in Denmark.

Birmingham has already been shamed as the fattest city in Europe, with more than one in five city adults classed as obese along with 13 per cent of children aged four to five.

The senior doctor agreed with Prime Minister David Cameron that “drastic action” was needed to save lives as the weight crisis worsened.

But Mr Taheri, who is also a University of Birmingham lecturer, said: “A big problem is that unhealthy food is cheaper than other foods.

“If you put a high tax on fatty food, you don’t know how it will pan out as you need to bring the price of healthy food down too, to encourage people to eat it.

Danish consumers have criticised the step, while retailers have complained about excessive bureaucracy.

Mr Cameron said: “The problem in the past when people have looked at using the tax system in this way is the impact it can have on people on low incomes. But, frankly, do we have a problem with the growing level of obesity? Yes.”

The Prime Minister added: “I am worried about the costs to the health service, the fact that some people are going to have shorter lifespans than their parents.

“Don’t rule anything out, but let’s look at the evidence and let’s look at the impact on families.”

n CHILDREN whose parents are thin are likely to be very slim themselves due to “skinny genes”, new research suggested.

A five-year study, published in the journal Archives of Paediatrics and Adolescent Medicine, claimed thinness may be inherited.

Youngsters whose parents are at the lower end of the healthy weight range are three times more likely to be regarded as thin than those whose parents are overweight.